Organic electroluminescent materials and devices

Abstract

Organometallic compounds comprising an imidazole carbene ligand having a N-containing ring fused to the imidazole ring are provided. In particular, the N-containing ring fused to the imidazole ring may contain one nitrogen atom or more than one nitrogen atom. These compounds may demonstrate high photoluminescent (PL) efficiency, Gaussian emission spectra, and/or short excited state lifetimes. These materials may be especially useful as blue phosphorescent emitters.

The invention claim is: 
     
       1. A compound selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
       2. A first device comprising an organic light emitting device, comprising:
 an anode; 
 a cathode; and 
 an organic layer, disposed between the anode and the cathode, wherein the organic layer comprises a compound selected from the group consisting of: 
 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
       3. The first device of  claim 2 , wherein the organic layer is an emissive layer and the compound is an emissive dopant. 
     
     
       4. The first device of  claim 3 , wherein the organic layer further comprises a host. 
     
     
       5. The first device of  claim 4 , wherein the host comprises at least one of the chemical groups selected from the group consisting of: 
       
         
           
           
               
               
           
         
         wherein each of R″′ 1  and R″′ 2  are independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; 
         wherein k is an integer from 0 to 20; and 
         wherein each of X 1 , X 2 , X 3 , X 4 , X 5 , X 6 , X 7  and X 8  are independently selected from the group consisting of CH and N. 
       
     
     
       6. The first device of  claim 4 , wherein the host is a metal complex. 
     
     
       7. The first device of  claim 2 , wherein the first device is a consumer product selected from the group consisting of flat panel displays, computer monitors, televisions, billboards, lights for interior or exterior illumination and/or signaling, heads up displays, fully transparent displays, flexible displays, laser printers, telephones, cell phones, personal digital assistants (PDAs), laptop computers, digital cameras, camcorders, viewfinders, micro-displays, vehicles, wall, theater or stadium screens, and signs. 
     
     
       8. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       9. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       10. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       11. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       12. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       13. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       14. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       15. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       16. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       17. The compound of  claim 1 , wherein the compound is 
       
         
           
           
               
               
           
         
       
     
     
       18. The compound of  claim 1 , wherein the compound is